LONDON — Buy now, pay later firm Affirm launched Monday its installment loans in the U.K., in the company’s first expansion overseas.

Founded in 2012, Affirm is an American fintech firm that offers flexible pay-over-time payment options. The company says it underwrites every individual transaction before making a lending decision, and doesn’t charge any late fees.

Affirm, which is authorised by the Financial Conduct Authority, said its U.K. offering will include interest-free and interest-bearing monthly payment options. Interest on its plans will be fixed and calculated on the original principal amount, meaning it won’t increase or compound.

The company’s expansion to the U.K. marks the first time it is launching in a market outside the U.S. and Canada. Globally, Affirm counts over 50 million users and more than 300,000 active merchants, including Amazon, Shopify and Walmart.

Among the first merchants offering Affirm as a payment method in the U.K. are Alternative Airlines, the flight booking website, and payments processing firm Fexco. Affirm said it expects to onboard more brands over the coming months.

Max Levchin, CEO of Affirm, told CNBC that the company had been working on its launch in the U.K. for over a year. The reason Affirm chose Britain as its first overseas expansion target was because it saw a lot of demand from merchants in the country, according to Levchin.

“It is a huge market, it’s English-speaking,” making it a great fit for the business, Levchin said in an interview last week ahead of Affirm’s U.K. launch. Affirm will eventually expand into other markets that aren’t English-speaking but this will take more work, he added.

“There are lots of competitors here who are doing a sensible job serving the market. But when we started doing merchant outreach, just to find out locally, is the market saturated? Does everybody feel well served?” Levchin said. “We got such an enormous amount of market pull. It kind of sealed the deal for us.”

Competition is fierce in the U.K. financial technology space. In the buy now, pay later segment Affirm focuses on, the company will find no shortage of competition in the form of sizable players like Klarna, Block’s Clearpay, Zilch, and PayPal, which entered the BNPL market in 2020.

Where Affirm differs to some of those players, according to Levchin, is that its range of financing products offer customers the ability to pay purchases off over much lengthier periods. For example, Affirm offers payment programs that last as long as 36 months.

Affirm’s launch in the U.K. comes as the government is consulting on plans to regulate the buy now, pay later industry.

Among the key measures the government is considering, is plans to require BNPL providers to provide clear information to consumers, ensure people aren’t paying more than they can afford, and give customers rights for when issues arise.

“Generally speaking, we welcome regulation that is thoughtful, that pushes the work onto the market to do the right thing, but also knows how not to be too cumbersome on the end-customer,” Levchin said.

“Telling us do lots of work in the background before you lend money is great. We’re very good at automating. We’re very good at writing software. We’ll go do the work,” he added. “Pushing the onus on the consumer is dangerous.”

Affirm secured authorization from the Financial Conduct Authority, the country’s financial services watchdog, after months of discussions with the regulator, Levchin said. He added that the firm’s “pristine reputation” helped.

“We’ve never charged a penny of late fees. We don’t do deferred interest. We don’t do any sort of the anti-consumer stuff people struggle with,” Levchin told CNBC. “So we have this good, untarnished reputation of being just very thoughtfully pro-consumer. And merchants love that.”